The people responsible for this situation were mostly the Gods and the Devils. Among the rank 11 powerhouses, the Supreme Magus from the humanoids actually wanted more people from his race to reach his same levels and assist him. That way, there was a possibility that his Sora could even rival the Celesta and the Helius.
But unfortunately for him, both the Gods and the Devils did not want the current power balance to be destroyed. They obviously did not want this long lasting battle between both of them to become a three way battle with another world getting involved.
So using their superior knowledge and various mysterious abilities, they managed to manipulate one of Supreme Magus's closest friend and use that person against him.
This friend of his head reached the rank of 11 but then, instead of working together with the Supreme Magus, this person instead tried to destroy all humanoids for the sake of a mad experiment.
